A conventional disc device is typically constructed in such a way that a slider member having a rack is driven to an operating position by a gear engaged with this rack, and is also driven from the operating position to a standby position, and a spring is mounted, as a pushing member, to the slider member in order to move the slider member to the standby position after the engagement between the rack and the gear is released while the slider member moves to the standby position, as described in, for example, patent reference 1.    [Patent reference 1] JP,2004-199831,A gazette
A problem with the conventional disc device is however that because only the spring force of the spring serves as the means for moving the slider member to the standby position after the engagement between the rack and the gear is released, as mentioned above, the slider member cannot move to the standby position when the load against the movement of the slider member exceeds the spring force of the spring because of, for example, a variation in the driving force of the gear at the time when the driving force is converted to the spring force of the spring.
A further problem is that even in a case in which the slider member is on standby at the standby position, when a shock exceeding the above-mentioned spring force of the spring is applied to the slider member due to a drop or the like of the disc device at the time of transfer, the slider member moves and collides with another member and is then damaged, or a displacement occurs in the slider member and the slider member therefore cannot operate normally at the time of start of the operation of the disc device.
Therefore, in order to solve the above-mentioned problems, there can be considered a measure of strengthening the spring force of the spring, or a measure of disposing a counteractive member for exclusive use or the like. However, in order to drive the slider member whose movement load is increased, a motor having a large driving force has to be adopted, and hence the disc device increases in size inevitably. A further problem is that provision of a counteractive member for exclusive use increases the cost of the disc device.
The present invention is made in order to solve the above-mentioned problems, and solves the problem that the slider member cannot return to its standby position by using a rotational force of a roller base member for moving a conveying roller to a disk conveying position to place the conveying roller in a standby state. It is an object of the present invention to provide a disc device that can prevent a slider member thereof from being displaced from its standby position even when a shock is applied to the slider member due to a drop or the like of the disc device at the time of transfer.